21,928 results on '"Calcium balance"'
Search Results
252. Chapter-24 Drugs Affecting Calcium Balance
- Author
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KD Tripathi
- Subjects
Calcium balance ,Chemistry ,Pharmacology - Published
- 2007
253. SP525TRANSPERITONEAL CALCIUM BALANCE WITH THE USE OF LOW-CALCIUM PERITONEAL DIALYSIS SOLUTION IN PERITONEAL DIALYSIS PATIENTS
- Author
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Luis M Pallardó, Belén Vizcaíno, Marco Montomoli, Sandra Beltrán, Ana Ávila, and Pablo Molina
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Transplantation ,medicine.medical_specialty ,Calcium balance ,business.industry ,medicine.medical_treatment ,Urology ,chemistry.chemical_element ,Calcium ,Low calcium ,Peritoneal dialysis ,chemistry ,Nephrology ,Medicine ,Peritoneal dialysis solutions ,business - Published
- 2015
254. Potassium citrate supplementation results in sustained improvement in calcium balance in older men and women
- Author
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Anthony Sebastian, Kendall F. Moseley, Connie M. Weaver, Lawrence J. Appel, and Deborah E. Sellmeyer
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Male ,medicine.medical_specialty ,Bone density ,Endocrinology, Diabetes and Metabolism ,Potassium ,chemistry.chemical_element ,Calcium ,Placebo ,Bone and Bones ,Article ,Bone remodeling ,Placebos ,Potassium Citrate ,Internal medicine ,medicine ,Humans ,Orthopedics and Sports Medicine ,Aged ,Calcium metabolism ,Middle Aged ,Endocrinology ,chemistry ,Alkaline phosphatase ,Female ,Net acid excretion - Abstract
The dietary acid load created by the typical Western diet may adversely impact the skeleton by disrupting calcium metabolism. Whether neutralizing dietary acid with alkaline potassium salts results in sustained improvements in calcium balance remains controversial. In this randomized, double-blind, placebo-controlled study, 52 men and women (mean age 65.2 ± 6.2 years) were randomly assigned to potassium citrate 60 mmol/d, 90 mmol/d, or placebo daily with measurements of bone turnover markers, net acid excretion, and calcium metabolism, including intestinal fractional calcium absorption and calcium balance, obtained at baseline and at 6 months. At 6 months, net acid excretion was significantly lower in both treatment groups compared to placebo and it was negative, meaning subjects' dietary acid was completely neutralized (-11.3 mmol/d on 60 mmol/d; -29.5 mmol/d on 90 mmol/d, p < 0.001 compared to placebo). At 6 months, 24-hour urine calcium was significantly reduced in persons taking potassium citrate 60 mmol/d (-46 ± 15.9 mg/d) and 90 mmol/d (-59 ± 31.6 mg/d) compared with placebo (p < 0.01). Fractional calcium absorption was not changed by potassium citrate supplementation. Net calcium balance was significantly improved in participants taking potassium citrate 90 mmol/d compared to placebo (142 ± 80 mg/d on 90 mmol/d versus -80 ± 54 mg/d on placebo; p = 0.02). Calcium balance was also improved on potassium citrate 60 mmol/d, but this did not reach statistical significance (p = 0.18). Serum C-telopeptide decreased significantly in both potassium citrate groups compared to placebo (-34.6 ± 39.1 ng/L on 90 mmol/d, p = 0.05; -71.6 ± 40.7 ng/L on 60 mmol/d, p = 0.02) whereas bone-specific alkaline phosphatase did not change. Intact parathyroid hormone was significantly decreased in the 90 mmol/d group (p = 0.01). Readily available, safe, and easily administered in an oral form, potassium citrate has the potential to improve skeletal health. Longer-term trials with definitive outcomes such as bone density and fracture are needed.
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- 2013
255. Effects of Calcitonin on Calcium Balance and Bone Resorption in Rainbow Trout, Oncorhynchus mykiss
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Björn Th. Björnsson, Yasuaki Takagi, Sigurdur Hilmir Johannsson, and Petra Persson
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medicine.medical_specialty ,Endocrinology ,History and Philosophy of Science ,Calcium balance ,Calcitonin ,Chemistry ,General Neuroscience ,Internal medicine ,medicine ,Rainbow trout ,General Biochemistry, Genetics and Molecular Biology ,Bone resorption - Published
- 1998
256. Impaired osteoblast function in osteoporosis: comparison between calcium balance and dynamic histomorphometry
- Author
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Pierre J. Meunier, C. Edouard, Robert M. Neer, J. Reeve, and M. Arlot
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Male ,medicine.medical_specialty ,Bone disease ,Osteoporosis ,Osteoclasts ,Cell Count ,Bone and Bones ,Bone resorption ,Bone remodeling ,Ilium ,Internal medicine ,medicine ,Humans ,Bone Resorption ,Aged ,General Environmental Science ,Minerals ,Osteomalacia ,Bone Development ,Osteoblasts ,Chemistry ,Osteoid ,General Engineering ,Osteoblast ,General Medicine ,Middle Aged ,medicine.disease ,Resorption ,Endocrinology ,medicine.anatomical_structure ,General Earth and Planetary Sciences ,Calcium ,Female ,Research Article - Abstract
Osteoblast function was investigated in 27 patients with idiopathic osteoporosis. Transiliac bone biopsy specimens were taken after double labelling with tetracycline, and metabolic calcium balance was studied almost simultaneously. Many of the patients showed poor double labelling of their otherwise unremarkable trabecular osteoid, suggesting impaired formation of bone at many of these surfaces. This phenomenon was not accompanied by increased width of osteoid seams (as seen in osteomalacia), indicating that formation of the matrix and its mineralisation were in equilibrium. For the first time, highly significant positive correlations (p less than 0.01) were found between indices of bone formation, determined by labelling with tetracycline, and calcium balance. Thus some patients with osteoporosis who are rapidly losing bone have low rates of formation of trabecular bone both by individual osteoblasts and in relation to available bone surfaces. As histological indices of bone resorption also independently correlated strongly and inversely (p less than 0.01) with calcium balance the rate of initiation of new basic multicellular units by osteoclastic resorption of trabecular surfaces (or the depth of resorption at these surfaces) also appears to be an important determinant of mineral balance. The mechanisms that regulate the effective life span of mature osteoblasts require further investigation, particularly as some promising treatments that can increase trabecular bone volume in osteoporosis, such as parathyroid peptide hPTH (1-34) and sodium fluoride, must work through a reversal of osteoblastic depression.
- Published
- 2016
257. Calcium balance during human growth: evidence for threshold behavior
- Author
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Matkovic, Velimir and Heaney, Robert P.
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Calcium in the body -- Physiological aspects ,Calcium, Dietary -- Physiological aspects ,Nutrition -- Requirements ,Human skeleton -- Growth ,Food/cooking/nutrition ,Health - Abstract
Calcium balances performed on 519 individuals from birth to 30 years of age, derived from 34 published reports, were pooled by age group and the relationship between intake and balance for each group was compared at both extremes of the intake range. At all ages, from infancy through the young adult years, balance values tended to flatten and become constant at higher intakes, while at lower intakes balance was invariably highly correlated with intake. Threshold intakes and balances were estimated by fitting the data to a two-component, split, linear-regression model. The threshold values at which balance no longer rose with intake exceeded the US recommended dietary allowances for calcium for all the age groups concerned.
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- 1992
258. Effects of Gluten /Casein Ratio on Calcium Balance of Rats Fed High Protein Diet
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Maeda, Yoshiaki, Muramastu, Daiki, Yajima, Kastuhiko, and Suzuki, Hitoshi
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calcium ,gluten ,protein ,balance rat ,casein - Abstract
P(論文), http://www.tsc-05.ac.jp/pdf_library/2014.pdf
- Published
- 2014
259. Aging and Calcium Balance
- Author
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Robert P. Heaney
- Subjects
medicine.medical_specialty ,Endocrinology ,Calcium balance ,chemistry ,business.industry ,Internal medicine ,Osteoporosis ,medicine ,chemistry.chemical_element ,Healthy elderly ,Calcium ,business ,medicine.disease - Abstract
This chapter discusses the role of calcium balance in aging. Calcium balance is the resultant of several interacting forces, including nutrition, hormonal status, disuse, and general involution. Minimization of the structural impact of a negative calcium balance (that is, a depleted skeleton) requires a multifaceted approach, including, but not limited to, an adequate calcium intake. Because calcium utilization is inefficient even during growth; and becomes more so with age; calcium intake requirements are high, and rise with age. Intakes of calcium for healthy elderly persons should be in the range of 1400–1600 mg/day, and patients with osteoporosis being treated with bone active agents may need substantially more to realize the full benefit of their antiosteoporosis therapies. The goal of a high calcium intake in the elderly is both to make certain that inadequate calcium is not compounding the other negative factors influencing the aging skeleton. and to support any bone-building potential that may reside in current and future antiosteoporosis therapies.
- Published
- 1999
260. Calcium balance in normal individuals and in patients with chronic kidney disease on low- and high-calcium diets
- Author
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David Spiegel and Kate Brady
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Male ,Time Factors ,030232 urology & nephrology ,Elemental calcium ,Parathyroid hormone ,030204 cardiovascular system & hematology ,Kidney ,Severity of Illness Index ,Nutrition Policy ,0302 clinical medicine ,Homeostasis ,Vitamin D ,Cross-Over Studies ,Middle Aged ,mineral metabolism ,3. Good health ,medicine.anatomical_structure ,Nephrology ,Creatinine ,Female ,Kidney Diseases ,Secondary hyperparathyroidism ,Glomerular Filtration Rate ,Adult ,medicine.medical_specialty ,Colorado ,chemistry.chemical_element ,Calcium ,Article ,03 medical and health sciences ,Internal medicine ,medicine ,Vitamin D and neurology ,Humans ,parathyroid hormone ,Aged ,phosphate ,calcium ,business.industry ,Kidney metabolism ,medicine.disease ,Calcium, Dietary ,Endocrinology ,chemistry ,Chronic Disease ,business ,Biomarkers ,chronic kidney disease ,Kidney disease - Abstract
Calcium balance in chronic kidney disease is poorly understood as calcium deficiency is a stimulus for secondary hyperparathyroidism and consequent bone loss while calcium excess promotes extraosseous calcifications. To help resolve this, we evaluated calcium balance in normal individuals and in patients with chronic kidney disease (CKD) on daily diets containing 800 and 2000 mg elemental calcium. Both normal individuals and patients with late stage 3 and stage 4 CKD were in slightly negative to neutral calcium balance on the 800-mg calcium diet. Normal individuals were in modest positive calcium balance on the 2000-mg diet, while patients with CKD on the same diet were in marked positive calcium balance at least over the 9 days of study; and significantly greater than the normal individuals. Increased calcium intake significantly decreased 1,25-dihydroxy-vitamin D and intact parathyroid hormone levels but did not alter the serum calcium concentration. Thus, our findings have important implications for both preventing calcium deficiency and loading in individuals with late stage 3 and stage 4 CKD.
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- 2012
261. Antihypertensive effect of piperitenone oxide on spontaneously hypertensive rat by regulating calcium balance and reducing endothelin-1 secretion
- Author
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Lan, Wei, primary, Zhang, Hong Ping, additional, Wang, Ying, additional, Jiang, Min, additional, Li, Qian, additional, and An, Dongqing, additional
- Published
- 2017
- Full Text
- View/download PDF
262. Gender aspects of osteoporosis and their relationship to calcium balance
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Fomina, L A, primary and Zyabreva, I A, additional
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- 2017
- Full Text
- View/download PDF
263. Bone growth and calcium balance during simulated weightlessness in the rat
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Roer, Robert D and Dillaman, Richard M
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Life Sciences (General) - Abstract
Rats, age 28 days, experiencing tail suspension in modified metabolic cages for 1, 2, and 3 wk were compared with littermate controls. Food and water consumption, urinary and fecal Ca excretion, and serum Ca were measured; hearts, fore- and hindlimb bones, skulls, and mandibles were removed for determination of wet, dry, and ash weights and Ca concentration and for histological examination. Weight gain and Ca intake and excretion were the same for both groups; both displayed net Ca gain. Suspended rats had significantly lower wet, dry, and ash weights of femora and tibiae. Dry weights of the humeri and radii/ulnae were moderately higher, and the skull and mandible dry and ash weights were significantly higher in suspended than in control rats. Cortical thickness of the femur, but not humerus, was less in suspended rats. The data are consistent with the hypothesis that bone growth is influenced by the cardiovascular changes associated with tail suspension.
- Published
- 1990
264. Effects of High-Dose Vitamin D2 Versus D3 on Total and Free 25-Hydroxyvitamin D and Markers of Calcium Balance.
- Author
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Shieh A, Chun RF, Ma C, Witzel S, Meyer B, Rafison B, Swinkels L, Huijs T, Pepkowitz S, Holmquist B, Hewison M, and Adams JS
- Subjects
- Adult, Aged, Biomarkers blood, Case-Control Studies, Dose-Response Relationship, Drug, Homeostasis drug effects, Hormone Replacement Therapy, Humans, Middle Aged, Parathyroid Hormone blood, Vitamin D blood, Calcium blood, Cholecalciferol administration & dosage, Ergocalciferols administration & dosage, Vitamin D analogs & derivatives, Vitamin D Deficiency blood, Vitamin D Deficiency drug therapy
- Abstract
Context: Controversy persists over: 1) how best to restore low serum 25-hydroxyvitamin D (25D) levels (vitamin D2 [D2] vs vitamin D3 [D3]); 2) how best to define vitamin D status (total [protein-bound + free] vs free 25D); and 3) how best to assess the bioactivity of free 25D., Objective: To assess: 1) the effects of D2 vs D3 on serum total and free 25D; and 2) whether change in intact PTH (iPTH) is more strongly associated with change in total vs free 25D., Design: Participants previously enrolled in a D2 vs D3 trial were matched for age, body mass index, and race/ethnicity. Participants received 50 000 IU of D2 or D3 twice weekly for 5 weeks, followed by a 5-week equilibration period. Biochemical assessment was performed at baseline and at 10 weeks., Setting and Participants: Thirty-eight adults (19 D2 and 19 D3) ≥18 years of age with baseline 25D levels <30 ng/mL were recruited from an academic ambulatory osteoporosis clinic., Outcome Measures: Serum measures were total 25D, free 25D (directly measured), 1,25-dihydroxyvitamin D, calcium, and iPTH. Urine measure was fasting calcium:creatinine ratio., Results: Baseline total (22.2 ± 3.3 vs 23.3 ± 7.2 ng/mL; P = .5) and free (5.4 ± 0.8 vs 5.3 ± 1.7 pg/mL; P = .8) 25D levels were similar between D2 and D3 groups. Increases in total (+27.6 vs +12.2 ng/mL; P = .001) and free (+3.6 vs +6.2 pg/mL; P = .02) 25D levels were greater with D3 vs D2. Percentage change in iPTH was significantly associated with change in free (but not total) 25D, without and with adjustment for supplementation regimen, change in 1,25-dihydroxyvitamin D, and change in calcium., Conclusions: D3 increased total and free 25D levels to a greater extent than D2. Free 25D may be superior to total 25D as a marker of vitamin D bioactivity.
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- 2016
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- View/download PDF
265. Regional citrate anticoagulation in hemodialysis: an observational study of safety, efficacy, and effect on calcium balance during routine care.
- Author
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Singer RF, Williams O, Mercado C, Chen B, Talaulikar G, Walters G, and Roberts DM
- Abstract
Background: Regional citrate hemodialysis anticoagulation is used when heparin is contraindicated, but most protocols require large infusions of calcium and frequent intradialytic plasma ionized calcium measurements., Objectives: The objective of this study was to determine the safety, efficacy, and effect on calcium balance of regional citrate anticoagulation using sparse plasma ionized calcium sampling., Design: The design of this study was observational., Setting: The setting of this study was the hospital hemodialysis center., Patients: The subjects of this study were the hospital hemodialysis patients., Measurements: Dialysate calcium concentration by atomic absorption spectroscopy and total dialysate weight were used as measurements., Methods: Regional citrate anticoagulation was introduced using zero calcium dialysate, pre-dialyzer citrate infusion, and post-dialyzer calcium infusion. Infusions were adjusted based on pre- and post-dialyzer calcium measurements obtained at least twice during a 4-h dialysis. The protocol was simplified after the first 357 sessions to dispense with post-dialyzer calcium measurements. Heparin-anticoagulated sessions were performed using acetate-acidified 1.25 mmol/L calcium or citrate-acidified 1.5 mmol/L calcium dialysate. Calcium balance assessment was by complete dialysate recovery. Safety and efficacy were assessed prospectively using a point-of-care database to record ionized calcium and clinical events. Groups were compared using t test, ANOVA, Wilcoxon rank sum, or Kruskal-Wallis as appropriate., Results: Seventy-five patients received regional citrate-anticoagulated dialysis over 1051 dialysis sessions. Of these, 357 dialysis sessions were performed using the original citrate anticoagulation protocol and 694 using the simplified protocol. Dialysis was effective and safe. Only 3 dialyzers clotted; 1 patient suffered symptomatic hypercalcemia and none suffered symptomatic hypocalcemia. Calcium balance was assessed in 15 regional citrate-anticoagulated dialysis sessions and 30 heparin-anticoagulated sessions. The median calcium loss was 0.8 mmol/h dialyzed in both groups (p = 0.43), and end of treatment ionized calcium was the same in both groups (1.07 ± 0.04 mmol/L)., Limitations: Our findings for calcium balance, efficacy, and safety are valid only for the protocol studied, which excluded patient with severe liver dysfunction., Conclusions: Regional citrate dialysis can be performed safely and effectively using a sparse plasma calcium sampling protocol. The calcium balance induced by this protocol is not different to that seen in standard heparin-anticoagulated dialysis, but in the absence of prospective studies, it is unknown whether this is optimal for patient care.
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- 2016
- Full Text
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266. Ethanol Extract of Fructus ligustri lucidi Increased Circulating 1,25(OH) 2 D 3 Levels, but Did Not Improve Calcium Balance in Mature Ovariectomized Rats.
- Author
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Dong XL, Cao SS, Zhou LP, Denney L, Wong MS, and Feng HT
- Subjects
- 25-Hydroxyvitamin D3 1-alpha-Hydroxylase genetics, 25-Hydroxyvitamin D3 1-alpha-Hydroxylase metabolism, Animals, Bone and Bones metabolism, Female, Fruit chemistry, Gene Expression drug effects, Humans, Kidney Tubules, Proximal cytology, Kidney Tubules, Proximal metabolism, Models, Animal, Rats, Sprague-Dawley, Up-Regulation drug effects, Vitamin D3 24-Hydroxylase genetics, Vitamin D3 24-Hydroxylase metabolism, Water, Calcitriol metabolism, Calcium metabolism, Ethanol, Ligustrum chemistry, Ovariectomy, Plant Extracts isolation & purification, Plant Extracts pharmacology
- Abstract
Our previous studies found that different extracts or fractions of Fructus ligustri lucidi (FLL) played different roles in altering the regulation of bone and mineral metabolism in different animal models. The present study was designed to compare the actions of FLL ethanol (EE) and water extracts (WE) on bone and mineral metabolism in a 6-month-old mature ovariectomized (OVX) rat model. Our results showed that FLL extracts did not significantly improve systematic Ca balance in mature OVX rats. However, EE, but not WE treatment, significantly increased serum 1,25(OH)
2 D3 levels in mature OVX rats. An in vitro study using human proximal tubule (HKC-8) cells showed that EE, but not WE, significantly enhanced renal 25-dihydroxyvitamin D3 -1[Formula: see text]-hydroxylase (1-OHase) mRNA expressions and simultaneously repressed renal 25-dihydroxyvitamin D3 -24-hydroxylase (24-OHase) mRNA expressions. Further investigation indicated that EE could significantly induce the protein expression of 1-OHase, but did not alter 24-OHase expression in HKC-8 cells. Our results demonstrated that EE increased circulating 1,25(OH)2 D3 levels in OVX rats, possibly via upregulation of renal 1-OHase expressions in renal proximal tubule cells. Our study indicates that FLL is a natural oral agent that could directly regulate renal vitamin D metabolism in vivo and in vitro.- Published
- 2016
- Full Text
- View/download PDF
267. Calcium Balance
- Author
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Mazyar Kanani
- Subjects
Surgical critical care ,medicine.medical_specialty ,Calcium balance ,business.industry ,Critical care nursing ,Intensive care ,medicine ,Pain management ,Intensive care medicine ,business - Published
- 2002
268. Ethanol Extract of Fructus ligustri lucidi Increased Circulating 1,25(OH)2D3 Levels, but Did Not Improve Calcium Balance in Mature Ovariectomized Rats.
- Author
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Dong, Xiao-Li, Cao, Si-Si, Zhou, Li-Ping, Denney, Liya, Wong, Man-Sau, and Feng, Hao-Tian
- Subjects
- *
ANIMAL experimentation , *CALCIUM , *DIET , *ENZYME-linked immunosorbent assay , *POLYMERASE chain reaction , *RATS , *RESEARCH funding , *STATISTICS , *T-test (Statistics) , *WESTERN immunoblotting , *PLANT extracts , *DATA analysis , *CHOLECALCIFEROL , *IN vitro studies , *ONE-way analysis of variance - Abstract
Our previous studies found that different extracts or fractions of Fructus ligustri lucidi (FLL) played different roles in altering the regulation of bone and mineral metabolism in different animal models. The present study was designed to compare the actions of FLL ethanol (EE) and water extracts (WE) on bone and mineral metabolism in a 6-month-old mature ovariectomized (OVX) rat model. Our results showed that FLL extracts did not significantly improve systematic Ca balance in mature OVX rats. However, EE, but not WE treatment, significantly increased serum 1,25(OH)2D3 levels in mature OVX rats. An in vitro study using human proximal tubule (HKC-8) cells showed that EE, but not WE, significantly enhanced renal 25-dihydroxyvitamin D3-1-hydroxylase (1-OHase) mRNA expressions and simultaneously repressed renal 25-dihydroxyvitamin D3-24-hydroxylase (24-OHase) mRNA expressions. Further investigation indicated that EE could significantly induce the protein expression of 1-OHase, but did not alter 24-OHase expression in HKC-8 cells. Our results demonstrated that EE increased circulating 1,25(OH)2D3 levels in OVX rats, possibly via upregulation of renal 1-OHase expressions in renal proximal tubule cells. Our study indicates that FLL is a natural oral agent that could directly regulate renal vitamin D metabolism in vivo and in vitro. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
269. Meta-Analysis of the Effect of the Acid-Ash Hypothesis of Osteoporosis on Calcium Balance
- Author
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Suzanne Tough, Andrew W. Lyon, David A. Hanley, Michael Eliasziw, and Tanis R. Fenton
- Subjects
medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Osteoporosis ,chemistry.chemical_element ,Calcium ,Models, Biological ,Bone and Bones ,Bone remodeling ,Nutrient ,Internal medicine ,Humans ,Medicine ,Orthopedics and Sports Medicine ,Acid-Base Equilibrium ,Calcium metabolism ,Alkaline diet ,Clinical Trials as Topic ,business.industry ,medicine.disease ,Urinary calcium ,Endocrinology ,chemistry ,Regression Analysis ,Net acid excretion ,business ,Biomarkers - Abstract
The acid-ash hypothesis posits that protein and grain foods, with a low potassium intake, produce a diet acid load, net acid excretion (NAE), increased urine calcium, and release of calcium from the skeleton, leading to osteoporosis. The objectives of this meta-analysis were to assess the effect of changes in NAE, by manipulation of healthy adult subjects' acid-base intakes, on urine calcium, calcium balance, and a marker of bone metabolism, N-telopeptides. This meta-analysis was limited to studies that used superior methodological quality for the study of calcium metabolism. We systematically searched the literature and included studies if subjects were randomized to the interventions and followed the recommendations of the Institute of Medicine's Panel on Calcium and Related Nutrients for calcium studies. Five of 16 studies met the inclusion criteria. The studies altered the amount and/or type of protein. Despite a significant linear relationship between an increase in NAE and urinary calcium (p < 0.0001), there was no relationship between a change of NAE and a change of calcium balance (p = 0.38; power = 94%). There was no relationship between a change of NAE and a change in the marker of bone metabolism, N-telopeptides (p = 0.95). In conclusion, this meta-analysis does not support the concept that the calciuria associated with higher NAE reflects a net loss of whole body calcium. There is no evidence from superior quality balance studies that increasing the diet acid load promotes skeletal bone mineral loss or osteoporosis. Changes of urine calcium do not accurately represent calcium balance. Promotion of the "alkaline diet" to prevent calcium loss is not justified.
- Published
- 2009
270. Calcium balance in haemodialysis—do not lower the dialysate calcium concentration too much (con part)
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Malik Touam and Tilman B. Drüeke
- Subjects
Transplantation ,medicine.medical_specialty ,Calcitriol ,Calcimimetic ,business.industry ,medicine.medical_treatment ,chemistry.chemical_element ,Parathyroid hormone ,Calcium ,Arterial calcification ,Endocrinology ,chemistry ,Nephrology ,Internal medicine ,Vitamin D and neurology ,medicine ,Hemodialysis ,business ,Dialysis ,medicine.drug - Abstract
The debate on the most adequate dialysate calcium concentration for intermittent haemodialysis therapy is ongoing. There is probably no one optimal concentration. In general, one would like to maintain a neutral calcium balance in adult haemodialysis patients. However, a slightly negative balance may be preferable to avoid soft-tissue calcium accumulation in face of net calcium loss from the bone with ageing. The problem with measurements of calcium balance is that they are generally imprecise, as are estimations of total body calcium and its distribution in various compartments, unless done with labour-intensive methods and great care. The choice of the dialysate calcium will depend on several factors, including parathyroid and vitamin D status, type and severity of concomitant bone disease, presence or absence of arterial calcification, dietary habits, drug treatment and dialysis modality. Ideally the dialysate calcium would be adapted to each patient's needs. This is not feasible, however, in most dialysis settings and neither is it cost-effective. From a practical point of view, a relatively high dialysate calcium concentration in the range of of 1.50-1.75 mmol/L (3.0-3.5 mEq/L) should probably be preferred in haemodialysis patients with high serum PTH levels who are not prescribed calcium-based phosphate binders or high doses of active vitamin D sterols, and in those who are receiving a calcimimetic. In those who are treated with high doses of calcium-based binders and/or active vitamin D derivatives or who have a very low serum PTH level, the optimal dialysate calcium concentration is probably lower, in the range of 1.25-1.50 mmol/L (2.50-3.0 mEq/L). In the present pro/con debate about the optimal dialysate calcium concentration used for the haemodialysis session, we have accepted to defend the viewpoint that a low calcium concentration may do more harm than benefit in many patients. This viewpoint is opposite to that taken by Gotch [1]. He argues that since calcitriol and other active vitamin D derivatives have become available virtually all haemodialysis patients are in positive calcium balance. We would like to take issue with this statement and warn against the indiscriminate use of a low calcium dialysate in all patients receiving haemodialysis therapy.
- Published
- 2009
271. 45Ca kinetics and calcium balance studies. A useful method for analyzing calcium movement as a whole throughout the entire body in rats
- Author
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Tomio Morohashi and Shoji Yamada
- Subjects
Pharmacology ,Calcium balance ,Chemistry ,Movement (music) ,Kinetics ,chemistry.chemical_element ,Anatomy ,Calcium ,Skeleton (computer programming) ,Bone and Bones ,Bone remodeling ,Resorption ,Rats ,Biophysics ,Methods ,Animals ,Female ,Bone Resorption ,Compartment (pharmacokinetics) - Abstract
45Ca kinetics and calcium balance studies allow for the simultaneous determination of calcium movement in the intestines, kidneys and bones. Since the flow of minerals in each of these organs depends on those in other organs, it is important to evaluate calcium movement as a whole throughout the entire body. Morphological methods can be used to evaluate local bone formation and resorption microscopically within defined windows. However, bone remodeling does not proceed equally in every part of the skeleton, and local events tend to be misread as general phenomena. Although variables such as bone formation and resorption obtained in 45Ca kinetics and calcium balance studies tell nothing about the location of these events, and the concept of compartments can be somewhat difficult to understand, this method is still useful for obtaining quite reliable results compared to those obtained by other methods. Our review describes the concept of the compartment model and explains the pertinent methods in comparison with other methods.
- Published
- 1997
272. EFFETTO DI DIFFERENTI CONCENTRAZIONI DI CALCIO NEL DIALISATO SULL'ORMONE PARATIROIDEO E SUL BILANCIO DEL CALCIO NELLA BICARBONATODIALISI.
- Author
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Basile, Carlo, Libutti, Pasquale, Lisi, Piero, Vernaglione, Luigi, Casucci, Francesco, Losurdo, Nicola, Teutonico, Annalisa, and Lomonte, Carlo
- Published
- 2011
273. The Sodium-Calcium Balance as a Function of Nerve Excitability and Cell Permeability (Abstract)
- Author
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Hall, J. Lowe
- Published
- 1929
- Full Text
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274. Fructus ligustri lucidi extract improves calcium balance and modulates the calciotropic hormone level and vitamin D-dependent gene expression in aged ovariectomized rats
- Author
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Chun-Tao Che, Man Sau Wong, Xiao-Li Dong, Ping-Chung Leung, and Yan Zhang
- Subjects
Vitamin ,medicine.medical_specialty ,Ovariectomy ,chemistry.chemical_element ,Parathyroid hormone ,Calcium ,Calcitriol receptor ,Phosphorus metabolism ,Excretion ,chemistry.chemical_compound ,Internal medicine ,medicine ,Vitamin D and neurology ,Animals ,Cholecalciferol ,business.industry ,Obstetrics and Gynecology ,Phosphorus ,Rats ,Calcium, Dietary ,Disease Models, Animal ,Endocrinology ,chemistry ,Parathyroid Hormone ,Ovariectomized rat ,Receptors, Calcitriol ,Female ,business ,Drugs, Chinese Herbal - Abstract
Objective: Fructus ligustri lucidi (FLL) is a widely used herb in China that is classically included in antiaging formulas for the treatment of age-related symptoms. Our laboratory previously showed that FLL could regulate calcium balance in young ovariectomized (OVX) rats. In the present study, we aimed to determine whether FLL could regulate calcium balance in aged OVX rats and to study the potential mechanisms that mediate its action in vivo. Design: Aged OVX rats were orally administered an ethanol extract of FLL and its vehicle and fed with diets containing different levels of calcium [low calcium diet (LCD), 0.1% Ca; medium calcium diet (MCD), 0.6% Ca; and high calcium diet (HCD), 1.2% Ca] for 12 weeks. Results: Significant reductions in urinary and fecal calcium excretion were found in the FLL-treated animals, resulting in a significant induction of calcium retention in rats fed with the MCD and HCD. FLL treatment significantly increased the serum 1,25-dihydroxyvitamin D 3 level and slightly decreased the serum parathyroid hormone level in OVX rats fed with the MCD and HCD. When OVX rats were challenged by LCD, the inductions of serum parathyroid hormone and 1,25-dihydroxyvitamin D 3 were decreased by FLL administration. FLL treatment significantly up-regulated duodenal vitamin D receptor and calcium transport protein 1 mRNA expression in rats fed with the HCD. FLL treatment reduced the expression of renal vitamin D receptor and 25-hydroxyvitamin D-24-hydroxylase mRNA in OVX rats fed with the LCD and MCD. Conclusions: Twelve weeks of FLL treatment could reduce calcium loss, modulate the parathyroid hormone-vitamin D axis, and increase vitamin D-dependent calcium transport in aged OVX rats, suggesting that FLL might be useful as an alternative medicine for improving calcium balance in postmenopausal women.
- Published
- 2008
275. Plant protein and calcium balance
- Author
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Ajayi, Olufunmike A.
- Published
- 1977
- Full Text
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276. Calcium balance in 1–4-y-old children
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Maria G. Hamzo, Steven A. Abrams, Mary Frances Lynch, Ian J. Griffin, Zhensheng Chen, and Keli M. Hawthorne
- Subjects
medicine.medical_specialty ,Birth weight ,Medicine (miscellaneous) ,chemistry.chemical_element ,Calcium ,Intestinal absorption ,law.invention ,Nutrient ,Animal science ,Randomized controlled trial ,Reference Values ,law ,Internal medicine ,medicine ,Birth Weight ,Humans ,Calcium metabolism ,Bone growth ,Bone Development ,Nutrition and Dietetics ,Infant, Newborn ,Infant ,United States ,Diet ,Bioavailability ,Calcium, Dietary ,Endocrinology ,Intestinal Absorption ,chemistry ,Child, Preschool - Abstract
Few calcium balance data are available from young children on which to base dietary recommendations.The objective of the study was to evaluate the relation between calcium intake and balance in healthy children aged 1-4 y consuming typical American diets.Subjects were assigned to a diet with nutrient intakes similar to those of their usual diet. Calcium absorption was assessed by using a dual-tracer stable-isotope technique. Endogenous fecal excretion was measured in a subset of children, and net calcium balance was calculated.Mean calcium intake was 551 mg/d (range: 124-983 mg/d), and mean (+/-SEM) calcium retention was 161 +/- 17 mg/d. Both linear and nonlinear modeling of balance data showed that a calcium intake of approximately 470 mg/d led to calcium retention of 140 mg/d, which is the amount that meets expected bone growth needs in children of this age. No evidence was found that calcium intakes of 800 to 900 mg/d reached the threshold intake beyond which no additional increase in calcium retention would occur.Bone growth needs in 1-4-y-old children following American diets are met by a daily calcium intake of approximately 470 mg/d, which suggests that the current Adequate Intake of 500 mg/d is close to the actual Estimated Average Requirement. The benefits and risks of higher calcium intakes consistent with threshold values should be evaluated in a controlled trial before those intakes could be used as a basis for dietary recommendations.
- Published
- 2007
277. Calcium balance in Daphnia grown on diets differing in food quantity, phosphorus and calcium.
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XUE-JIA HE and WEN-XIONG WANG
- Subjects
- *
CALCIUM , *DAPHNIIDAE , *CUTANEOUS horns , *DAPHNIA magna , *RADIOACTIVE tracers , *PHOSPHORUS , *FRESHWATER biology , *INSECT development , *TRACERS (Chemistry) - Abstract
1. The influences of dietary phosphorus (P) and food concentration on the calcium (Ca) balance in Daphnia magna were examined in this study at two different ambient Ca concentrations (0.5 and 10 mg Ca L−1). Daphnia were grown by feeding the young adults differentially under contrasting dietary P conditions [molar C : P ratio = c. 900 and c. 90 as low P (LP) and high P (HP), respectively], ambient Ca concentrations [0.5 mg and 10 mg Ca L−1 as low Ca (LCa) or high Ca (HCa), respectively] and food levels [0.15 or 1.5 mg C L−1 as low food (LF) or high food (HF), respectively] for 5 days. 2. The specific Ca contents of daphniids (1.9–6.5% of dry weight−1) increased with increasing Ca concentration, food level and dietary P content, although the food level did not affect the Ca content in the HPHCa treatment. A radioactive tracer method showed that the food level did not affect the influx of Ca from the water under LP conditions, but the Ca influx under HP conditions doubled with a HF level. A LP condition also led to a decrease in Ca influx with a HF level. 3. During the 3 days of efflux, generally only a small proportion of Ca (2.6–3.3%) was retained by the daphniids, but this retention increased (14–23%) under low ambient Ca concentrations and under P-limitation. Excretion was the most important pathway for Ca loss (accounting for 50–60% of body Ca), followed by moulting (20–47%), but the relative contribution of these two pathways (excretion and moulting) did not vary among all the different treatments. The absolute loss of Ca through excretion and moulting, on the contrary, differed with different ambient Ca concentrations and dietary P conditions. A HF level led to an increase in the loss rates in most cases. 4. Our study strongly suggested that there is an interaction between an essential metal (Ca) and macronutrients (C and P) in freshwater crustaceans with HCa and P contents. The results imply that variation in environmental nutrient conditions may change the Ca budget in crustaceans and may affect the dynamics of Ca in the epilimnion of freshwaters. [ABSTRACT FROM AUTHOR]
- Published
- 2009
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278. Calcimimetics, calcium set point and calcium balance
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Angela Marino and Nicola Giotta
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Transplantation ,Calcium balance ,business.industry ,Naphthalenes ,Parathyroid Hormone ,Renal Dialysis ,Nephrology ,Biophysics ,Humans ,Medicine ,Calcium set point ,Calcium ,Hyperparathyroidism, Secondary ,Cinacalcet ,business - Published
- 2008
279. Oophorectomy in young rats impairs calcium balance by increasing intestinal calcium secretion
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Peter D. O’Loughlin and Howard A. Morris
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medicine.medical_specialty ,Aging ,Calcium balance ,medicine.medical_treatment ,Ovariectomy ,Medicine (miscellaneous) ,chemistry.chemical_element ,Calcium ,Excretion ,Rats, Sprague-Dawley ,Internal medicine ,medicine ,Animals ,Secretion ,Intestinal Mucosa ,Calcium metabolism ,Nutrition and Dietetics ,Chemistry ,Body Weight ,Oophorectomy ,Urinary calcium ,Rats ,Calcium, Dietary ,Endocrinology ,Intestinal Absorption ,Female ,Analysis of variance - Abstract
Calcium balance and its major components (true calcium absorption, urinary calcium excretion and intestinal calcium secretion) were assessed by a 6-d balance technique in young (6-wk-old) rats fed a diet containing 7.2 g Ca/kg diet. Following either oophorectomy (oophx) or sham operation, the balance study was repeated at 9, 12 and 15 wk of age. Calcium balance decreased with age but remained positive in each group [mean (pooled SEM): sham, (6 wk) 0.86 to (15 wk) 0.27 (0.03) mmol/d (P < 0.0001); oophx, (6 wk) 0.91 to (15 wk) 0.22 (0.03) mmol/d (P < 0.0001)]. Analysis of variance of the change in calcium balance indicated that there was a significantly greater reduction in calcium balance in the oophx group compared with the sham-operated group. Intestinal calcium absorption decreased in each group with age [sham: (6 wk) 46.3% to (15 wk) 22.6% (1.5%) (P < 0.0001); oophx: (6 wk) 48.2% to (15 wk) 21.2% (1.5%) (P < 0.0001)]. There was a marked rise in intestinal calcium secretion in the oophx group compared with the sham-operated group at 6 wk post-operation (12 wk of age) [oophx: 0.33 (0.02) mmol/d; sham: 0.23 (0.02) mmol/d (P < 0.01)]. Urinary calcium excretion was not affected by either age or oophorectomy. We conclude that oophorectomy in young rats leads to a reduction in calcium accumulation, which is mainly the result of an increase in intestinal calcium secretion.
- Published
- 1994
280. Calcium balance and serum ionized calcium fluctuations in on-line haemodiafiltration in relation to ultrafiltration rate and dialysate calcium concentration
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B. Corradi, C Tetta, Fabio Malberti, and Enrico Imbasciati
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Calcium metabolism ,Transplantation ,Chromatography ,Calcium balance ,business.industry ,Ultrafiltration ,chemistry.chemical_element ,Electrolyte ,Calcium ,Hemodialysis Solutions ,chemistry ,Biochemistry ,Nephrology ,Weight loss ,Infusion Procedure ,Medicine ,medicine.symptom ,business - Abstract
The use of high ultrafiltration rates in haemodiafiltration (HDF) has been suggested for improving the clearance of small and large molecules. This strategy has become economically applicable with the development of safe techniques for on-line production of sterile infusate from dialysate, which enables us to infuse large substitution fluid volumes without further increasing the cost of sessions. The effect of increasing the ultrafiltration rate in HDF on electrolyte balance has not yet been evaluated. The aim of this study was to evaluate the effects of variations of the ultrafiltration rate on calcium kinetics in HDF using three different dialysate calcium concentrations. Since the increase in ultrafiltration rate augments the convective calcium loss, variations of intrasession calcium balance could result from modifications of the ultrafiltration rate. In the present study we found no significant variations in calcium balance and serum ionized calcium (iCa) levels during on-line HDF treatment when increasing the mean ultrafiltration rate from 60 to 100 ml/min in the presence of an adequate and corresponding increase in the infusion rate (from 2.5 to 5 l/h). During the balance studies, pretreatment serum iCa was on the average 1.32 mmol/l and weight loss 3.2 kg. Mean calcium loss during treatment was 2.8 and 3.3 mmol at infusion rates of 2.5 and 5 l/h with 1.63 mmol/l of calcium in both the dialysate and infusate; calcium loss rose to 5.9 and 11.2 mmol at infusion rates of 2.5 l/h and to 5.7 and 14.2 mmol at infusion rates of 5 l/h when the dialysate and infusate calcium was reduced respectively to 1.5 and 1.25 mmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1994
281. Calcium requirements for Chinese adults by cross-sectional statistical analyses of calcium balance studies: an individual participant data and aggregate data meta-regression
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Aiping, Fang, Keji, Li, Haoyu, Shi, Jingjing, He, and He, Li
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Adult ,Calcium, Dietary ,Cross-Sectional Studies ,Nutritional Requirements ,Humans ,Calcium - Abstract
Chinese dietary reference intakes for calcium are largely based on foreign studies. We undertook meta-regression to estimate calcium requirements for Chinese adults derived from calcium balance data in Chinese adults.We searched PubMed, Cochrane CENTRAL, and SinoMed from inception to March 5, 2014, by using a structured search strategy. The bibliographies of any relevant papers and journals were also screened for potentially eligible studies. We extracted a standardized data set from studies in Chinese adults that reported calcium balance data. The relationship between calcium intake and output was examined by an individual participant data (IPD) and aggregate data (AD) meta-regression.We identified 11 metabolic studies in Chinese adults within 18-60 years of age. One hundred and forty-one IPD (n = 35) expressed as mg/d, 127 IPD (n = 32) expressed as mg×kg body wt(-1)×d(-1), and 44 AD (n = 132) expressed as mg/d were collected. The models predicted a neutral calcium balance (defined as calcium output (Y) equal to calcium intake (C)) at intakes of 460 mg/d (Y = 0.60C+183.98) and 8.27 mg×kg body wt(-1)×d(-1) (Y = 0.60C+3.33) for IPD, or 409 mg/d (Y = 0.66C+139.00) for AD. Calcium requirements at upper intakes were higher than that at lower intakes in all these models.Calcium requirement for Chinese adults 18-60 years of age approximately ranges between 400 mg/d and 500 mg/d when consuming traditional plant-based Chinese diets.
- Published
- 2014
282. Effects of Vitamin D Supplementation on Calcium Balance and Bone Growth in Young Rats Fed Normal or Low Calcium Diet.
- Author
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Iwamoto, J., Yeh, J.K., Takeda, T., and Sato, Y.
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- *
VITAMIN D , *CALCIUM , *BONE growth , *LABORATORY rats , *STEROID hormones , *BONE marrow - Abstract
Objective: We examined the effect of vitamin D supplementation on bone growth in young rats fed a normal or low calcium diet. Methods: Fifty female Sprague-Dawley rats, 6 weeks of age, were randomized by stratified weight method into five groups with 10 rats in each group: baseline control, 0.5% (normal) or 0.1% (low) calcium diet, and 0.5 or 0.1% calcium diet + vitamin D (25 μg/100 g, food intake). Duration of the experiment was 10 weeks. Results: Vitamin D supplementation stimulated intestinal calcium absorption and increased urinary calcium excretion in rats fed a low or normal calcium diet. Vitamin D supplementation prevented the reduction in periosteal bone gain but enhanced enlargement of the marrow cavity and reduced the maturation-related cancellous bone gain in rats fed a low calcium diet, and increased the maturation-related cancellous and cortical bone gains in rats fed a normal calcium diet. Conclusion: This study shows the differential effects of vitamin D supplementation on born growth in young rats fed a normal or low calcium diet. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
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283. Soft drinks: bad to the bone? Examining the link between soft drink consumption and the body's calcium balance. (research update)
- Author
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Applegate, Liz
- Subjects
Osteoporosis -- Research ,Bones -- Health aspects ,Carbonated beverages -- Physiological aspects ,Caffeine -- Physiological aspects ,Health - Abstract
The word is out. One out of every two women and one in eight men will suffer from a debilitating bone fracture caused by osteoporosis. These staggering statistics have made [...]
- Published
- 2002
284. Effects of High-Dose Vitamin D2 Versus D3 on Total and Free 25-Hydroxyvitamin D and Markers of Calcium Balance
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Martin Hewison, Christina Ma, Albert Shieh, Briana Meyer, John S. Adams, Rene F. Chun, Tonnie Huijs, Brett Holmquist, Leon Maria Jacobus Wilhelmus Swinkels, Brandon Rafison, Sam Pepkowitz, and Sten Witzel
- Subjects
0301 basic medicine ,Vitamin ,Adult ,medicine.medical_specialty ,Hormone Replacement Therapy ,Endocrinology, Diabetes and Metabolism ,Clinical Biochemistry ,030209 endocrinology & metabolism ,Context (language use) ,Biochemistry ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Endocrinology ,Randomized controlled trial ,law ,Internal medicine ,Vitamin D and neurology ,Medicine ,Homeostasis ,Humans ,Vitamin D ,skin and connective tissue diseases ,Aged ,Cholecalciferol ,Creatinine ,Dose-Response Relationship, Drug ,business.industry ,Biochemistry (medical) ,Case-control study ,Original Articles ,Middle Aged ,Vitamin D Deficiency ,030104 developmental biology ,chemistry ,Parathyroid Hormone ,Case-Control Studies ,Ambulatory ,Ergocalciferols ,Calcium ,sense organs ,business ,Body mass index ,Biomarkers - Abstract
Controversy persists over: 1) how best to restore low serum 25-hydroxyvitamin D (25D) levels (vitamin D2 [D2] vs vitamin D3 [D3]); 2) how best to define vitamin D status (total [protein-bound + free] vs free 25D); and 3) how best to assess the bioactivity of free 25D.To assess: 1) the effects of D2 vs D3 on serum total and free 25D; and 2) whether change in intact PTH (iPTH) is more strongly associated with change in total vs free 25D.Participants previously enrolled in a D2 vs D3 trial were matched for age, body mass index, and race/ethnicity. Participants received 50 000 IU of D2 or D3 twice weekly for 5 weeks, followed by a 5-week equilibration period. Biochemical assessment was performed at baseline and at 10 weeks.Thirty-eight adults (19 D2 and 19 D3) ≥18 years of age with baseline 25D levels30 ng/mL were recruited from an academic ambulatory osteoporosis clinic.Serum measures were total 25D, free 25D (directly measured), 1,25-dihydroxyvitamin D, calcium, and iPTH. Urine measure was fasting calcium:creatinine ratio.Baseline total (22.2 ± 3.3 vs 23.3 ± 7.2 ng/mL; P = .5) and free (5.4 ± 0.8 vs 5.3 ± 1.7 pg/mL; P = .8) 25D levels were similar between D2 and D3 groups. Increases in total (+27.6 vs +12.2 ng/mL; P = .001) and free (+3.6 vs +6.2 pg/mL; P = .02) 25D levels were greater with D3 vs D2. Percentage change in iPTH was significantly associated with change in free (but not total) 25D, without and with adjustment for supplementation regimen, change in 1,25-dihydroxyvitamin D, and change in calcium.D3 increased total and free 25D levels to a greater extent than D2. Free 25D may be superior to total 25D as a marker of vitamin D bioactivity.
- Published
- 2016
285. Comparative Effects of Vitamin K and Vitamin D Supplementation on Calcium Balance in Young Rats Fed Normal or Low Calcium Diets
- Author
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Yoshihiro Sato, Tsuyoshi Takeda, Jun Iwamoto, and James K. Yeh
- Subjects
Vitamin ,medicine.medical_specialty ,Vitamin K ,Calcitriol ,Medicine (miscellaneous) ,Parathyroid hormone ,chemistry.chemical_element ,Calcium ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Internal medicine ,Menatetrenone ,medicine ,Vitamin D and neurology ,Animals ,Homeostasis ,Drug Interactions ,Vitamin D ,Calcium metabolism ,Nutrition and Dietetics ,Hypocalcemia ,Phosphorus ,Urinary calcium ,Rats ,Calcium, Dietary ,Endocrinology ,Intestinal Absorption ,chemistry ,Parathyroid Hormone ,Dietary Supplements ,Female ,medicine.drug - Abstract
We examined the effect of vitamin K and vitamin D supplementation on calcium balance in young rats fed a normal or low calcium diet. Eighty female Sprague-Dawley rats, 6 wk of age, were randomized by the stratified weight method into eight groups with 10 rats in each group: 0.5% (normal) or 0.1% (low) calcium diet, 0.5% or 0.1% calcium diet+vitamin K (vitamin K2, menatetrenone, 30 mg/100 g, food intake), 0.5% or 0.1% calcium diet+vitamin D (25 microg/100 g, food intake), and 0.5% or 0.1% calcium diet+vitamin K+vitamin D. The duration of the study was 10 wk. Vitamin K supplementation promoted the reduction in urinary calcium excretion and retarded the abnormal elevation of serum PTH level in rats fed a low calcium diet, and stimulated intestinal calcium absorption in rats fed a normal calcium diet. Vitamin D supplementation stimulated intestinal calcium absorption with prevention of the abnormal elevation of serum PTH levels and prevented hypocalcemia in rats fed a low calcium diet, and stimulated intestinal calcium absorption in rats fed a normal calcium diet. The stimulation of intestinal calcium absorption was associated with increased serum 1,25-dihydroxyvitamin D levels. An additive effect of vitamin K and vitamin D on intestinal calcium absorption was found only in rats fed a normal calcium diet. This study shows the differential effects of vitamin K and vitamin D supplementation on calcium balance in young rats fed a normal or low calcium diet.
- Published
- 2005
286. A pilot study on the use of natural calcium isotope ( 44Ca/ 40Ca) fractionation in urine as a proxy for the human body calcium balance
- Author
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Heuser, Alexander and Eisenhauer, Anton
- Published
- 2010
- Full Text
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287. Effects of Sigma Anti-bonding Molecule Calcium Carbonate on bone turnover and calcium balance in ovariectomized rats
- Author
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Goeun Yang, Dongsun Park, Ill Hwa Kim, So Young Choi, Hyun Gu Kang, Sun Hee Lee, Paul K Lee, Seock Yeon Hwang, Dae Kwon Bae, and Yun-Bae Kim
- Subjects
Bone mineral ,medicine.medical_specialty ,Bone density ,biology ,Osteoporosis ,17β-estradiol ,chemistry.chemical_element ,osteocalcin ,Calcium ,medicine.disease ,type I collagen C-terminal telopeptides ,Bone remodeling ,Endocrinology ,chemistry ,Internal medicine ,Osteocalcin ,biology.protein ,medicine ,Ovariectomized rat ,Original Article ,bone mineral density ,Sigma Anti-bonding Molecule Calcium Carbonate ,Type I collagen - Abstract
This study was conducted to evaluate the effect of Sigma Anti-bonding Molecule Calcium Carbonate (SAC) as therapy for ovariectomy-induced osteoporosis in rats. Three weeks after surgery, fifteen ovariectomized Sprague-Dawley rats were divided randomly into 3 groups: sham-operated group (sham), ovariectomized group (OVX) and SAC-treatment group (OVX+SAC). The OVX+SAC group was given drinking water containing 0.0012% SAC for 12 weeks. Bone breaking force and mineralization as well as blood parameters related to the bone metabolism were analyzed. In OVX animals, blood concentration of 17β-estradiol decreased significantly, while osteocalcin and type I collagen C-terminal telopeptides (CTx) increased. Breaking force, bone mineral density (BMD), calcium and phosphorus in femurs, as well as uterine and vaginal weights, decreased significantly following OVX. However, SAC treatment (0.0012% in drinking water) not only remarkably restored the decreased 17β-estradiol and increased osteocalcin and CTx concentrations, but also recovered decreased femoral breaking force, BMD, calcium and phosphorus, although it did not reversed reproductive organ weights. It is suggested that SAC effectively improve bone density by preventing bone turnover mediated osteocalcin, CTx and minerals, and that it could be a potential candidate for therapy or prevention of postmenopausal osteoporosis.
- Published
- 2011
288. Improvement of calcium balance byFructus Ligustri Lucidiextract in mature female rats was associated with the induction of serum parathyroid hormone levels
- Author
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Chun-Tao Che, Kwun Kit Wong, Xiao-Li Dong, Ming Zhao, and Man Sau Wong
- Subjects
medicine.medical_specialty ,Urinary system ,Ligustrum ,Osteoporosis ,Medicine (miscellaneous) ,chemistry.chemical_element ,Parathyroid hormone ,Calcium ,Phosphorus metabolism ,Rats, Sprague-Dawley ,Excretion ,Feces ,Bone Density ,Internal medicine ,Animals ,Medicine ,Bone mineral ,Calcium metabolism ,Nutrition and Dietetics ,business.industry ,Body Weight ,Phosphorus ,medicine.disease ,Rats ,Calcium, Dietary ,Endocrinology ,chemistry ,Parathyroid Hormone ,Female ,business ,Drugs, Chinese Herbal - Abstract
Fructus Ligustri Lucidi(FLL) is a commonly prescribed herb in many kidney-tonifying Traditional Chinese Medicinal formulae for the treatment of osteoporosis. The present study aimed to identify the active fractions in FLL and to characterise its effects on Ca balance, calciotropic hormone levels as well as bone properties in mature female rats fed diets containing different levels of Ca. In the present study, 4-month-old Sprague–Dawley female rats were treated with either FLL ethanol extract (EE), ethyl acetate-soluble fraction of EE (EAF), water-soluble fraction of EE (WF) or their vehicle for 12 weeks on a medium-Ca diet (MCD, 0·6 % Ca, 0·65 % P). Then, the Sprague–Dawley female rats treated with WF or its vehicle for 12 weeks were fed diets containing different levels of dietary Ca (low-Ca diet (LCD), 0·1 % Ca, 0·65 % P; MCD; high-Ca diet (HCD), 1·2 % Ca, 0·65 % P). The results demonstrated that WF from EE but not EAF exerted a prominent effect on Ca balance by inhibiting urinary and faecal Ca excretion. WF significantly increased Ca balance in rats fed MCD or HCD with an associated increase in serum parathyroid hormone (PTH) levels. WF did not alter bone mineral density or bone mineral content of the tibia in all the rats fed with different levels of dietary Ca. In conclusion, WF was responsible for the positive actions of FLL on Ca absorption and balance. The regulation of Ca balance by WF might involve its action in stimulating PTH production in the mature female rats.
- Published
- 2011
289. DISORDERS OF PHOSPHOrus-CALCium BALANCE IN PATIENTS ON CHRONIC HEMODIALYSIS - TIME-BASED DURATION RELATIONSHIP
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Branka Mitic, Vidojko Đorđević, Ivan Kostić, Jelena Kostić, Svetislav Kostić, and Petar Babović
- Subjects
hemodialysis ,calcium ,business.industry ,lcsh:R ,duration ,mineral and bone metabolism ,lcsh:Medicine ,Time based ,Industrial and Manufacturing Engineering ,Duration (music) ,Anesthesia ,Medicine ,In patient ,Chronic hemodialysis ,phosphorus ,Phosphorus calcium ,business ,PTH ,Balance (ability) - Abstract
Chronic renal failure (CRF) is a progressive, irreversible deterioration of kidney function that leads to complete loss of kidney function and the need for dialysis treatment. Bone disease is a chronic complication in the CRF and poses a significant problem in hemodialysis patients. The aim of our study was to assess the influence of peritoneal dialysis treatment on biochemical parameters of mineral and bone metabolism in hemodialysis patients, and identify the most important parameters for the monitoring of this disorder. The research involved 172 patients, mean age 58.69±12:54, divided into groups in respect to the length of dialysis treatment (group I - 5 years, group II - 5-10 years and group III - over 10 years). Serum phosphorus in all the patients was increased, but the values increased with duration of dialysis (I: 1.77±0.58, II: 1.97±0.66, III: 1.92±0.82), with no statistical differences (p>0.05). Calcemia values were significantly increased (I vs. II. and I vs. III, p
- Published
- 2011
290. Effects of Prolonged High Phosphorus Diet on Phosphorus and Calcium Balance in Rats
- Author
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Kaori Genjida, Hidekazu Arai, Hironori Yamamoto, Naoki Sawada, Tadatoshi Sato, Hisami Yamanaka-Okumura, Yutaka Taketani, Eiji Takeda, and Yoshiko Tani
- Subjects
medicine.medical_specialty ,food.ingredient ,Brush border ,Clinical Biochemistry ,Medicine (miscellaneous) ,Parathyroid hormone ,chemistry.chemical_element ,high phosphorus diet ,sodium-dependent phosphate transporter (Npt) ,Calcium ,parathyroid hormone (PTH) ,mature rat ,chemistry.chemical_compound ,Animal science ,food ,Internal medicine ,medicine ,Feces ,Nutrition and Dietetics ,Food additive ,Phosphorus ,phosphorus balance ,Phosphate ,Endocrinology ,chemistry ,Original Article ,Homeostasis - Abstract
The amount of phosphorus contained in food as food additives is currently increasing and a high intake of phosphorus can cause various diseases. To determine the effects of a prolonged high phosphorus diet, here we investigated the phosphorus and calcium balance and expression of type IIa sodium-dependent phosphate transporter (Npt IIa) in mature rats. Wistar male rats (8-weeks old) were divided into five groups and fed diets containing 0.6% calcium plus 0.3, 0.6, 0.9, 1.2 or 1.5% phosphorus for 4 weeks. Urinary and fecal phosphorus excretions were significantly increased by the high phosphorus diets (from 0.6 to 1.5%), dependent on the amount of dietary phosphorus. The net absorption of intestinal phosphorus was also significantly increased by high phosphorus diets. As a result, a negative phosphorus balance was observed in rats given the 1.2% or 1.5% phosphorus diets. Serum parathyroid hormone and 1,25-dihydroxyvitamin D(3) concentrations were increased by high phosphorus diets. In addition, high phosphorus diets decreased the expression of Npt IIa mRNA and protein in the renal brush border membrane. Taken together, these results suggest that diets containing 1.2 or 1.5% phosphorus plus 0.6% calcium have potentially adverse effects on phosphorus homeostasis in mature rat.
- Published
- 2007
291. Octreotide improves calcium balance in muscular dystrophy
- Published
- 1995
- Full Text
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292. Endogenous fecal losses of calcium compromise calcium balance in pancreatic-insufficient girls with cystic fibrosis
- Author
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Kerry Schulze, David J. Baer, Amanda Leonard, Kimberly O. O'Brien, Emily L. Germain-Lee, and Beryl J. Rosenstein
- Subjects
medicine.medical_specialty ,Pancreatic disease ,Adolescent ,Cystic Fibrosis ,chemistry.chemical_element ,Urine ,Calcium ,Cystic fibrosis ,Feces ,Bone Density ,Calcium Metabolism Disorders ,Internal medicine ,Humans ,Medicine ,Child ,Bone mineral ,business.industry ,medicine.disease ,Urinary calcium ,Bone Diseases, Metabolic ,Endocrinology ,chemistry ,Pediatrics, Perinatology and Child Health ,Female ,Bone Remodeling ,business ,Body mass index - Abstract
Objective Bone mineral density is compromised in individuals with cystic fibrosis (CF); calcium is the major bone mineral. This study examined the impact of endogenous fecal calcium (V endo ) losses on calcium balance in girls with CF. Study design V endo was measured in 12 girls with CF (aged 7-18 years): 7 younger, premenarcheal girls with compromised nutritional status; and 5 older, postmenarcheal girls with adequate nutritional status. V endo was measured as the amount of intravenously administered 42 Ca, a calcium stable isotope, in stool relative to urine over 6 days. V endo was compared between pre- and postmenarcheal girls by Student's t test. Actual calcium balance [absorbed calcium−(urinary calcium (V u )+V endo )] was compared with estimated balance (assuming V endo =1.6 mg/kg/day calcium) by paired t test. Results V endo was 99.3±42.3 mg/day. By body weight, V endo was highest among premenarcheal girls (3.37±1.09 mg/kg/day), resulting in excess losses (>1.6 mg/kg/day) of 55.0±45.7 mg/day. Over 1 year, this represents 20.1±16.7 g of unattained bone calcium or 6.7±4.2% of the bone calcium content of these girls. Conclusions V endo is a significant source of calcium loss in individuals with CF and may limit calcium availability for bone mineral deposition.
- Published
- 2003
293. Calcium balance and negative impact of calcium load in peritoneal dialysis patients.
- Author
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Wang AY
- Subjects
- Calcinosis prevention & control, Calcium administration & dosage, Dialysis Solutions metabolism, Disease Progression, Homeostasis physiology, Humans, Phosphates metabolism, Renal Insufficiency, Chronic metabolism, Risk Factors, Calcium metabolism, Peritoneal Dialysis, Renal Insufficiency, Chronic therapy
- Abstract
Like hemodialysis patients, peritoneal dialysis (PD) patients are facing an excessively increased burden of vascular and valvular calcification. According to some surveys, more than 80% of prevalent PD patients are complicated with vascular calcification, and more than one third have heart valve calcification. Dysregulated phosphate metabolism is well recognized to play an important role in inducing vascular calcification, but increasing evidence is suggesting that dysregulated calcium metabolism also promotes vascular calcification and might in fact be more potent than phosphate in inducing that calcification. Growing evidence from randomized controlled trials shows more progression of vascular calcification and higher mortality among chronic kidney disease (CKD) patients receiving calcium-based phosphate binders than among those receiving non-calcium-containing phosphate binders. Those results raise important safety concern about the use of high-dose calcium-based phosphate binders in the CKD population, including both non-dialysis and dialysis patients (especially anuric dialysis patients), who have markedly reduced urinary calcium excretion. To prevent calcium overload, this review recommends restricting the dose of calcium-based phosphate binders in CKD patients, especially those who are elderly, who have increased cardiovascular risk, who already have baseline vascular or valvular calcification, or who have low intact parathyroid hormone and adynamic bone disease., (Copyright © 2014 International Society for Peritoneal Dialysis.)
- Published
- 2014
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294. Stanniocalcin-1 controls ion regulation functions of ion-transporting epithelium other than calcium balance.
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Chou MY, Lin CH, Chao PL, Hung JC, Cruz SA, and Hwang PP
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- Animals, Calcium metabolism, Cell Differentiation, Chlorides metabolism, Embryo, Nonmammalian metabolism, Ion Transport physiology, Sodium metabolism, Zebrafish, Zebrafish Proteins genetics, Zebrafish Proteins metabolism, Epithelium drug effects, Epithelium metabolism, Glycoproteins pharmacology
- Abstract
Stanniocalcin-1 (STC-1) was first identified to involve in Ca(2+) homeostasis in teleosts, and was thought to act as a hypocalcemic hormone in vertebrate. Recent studies suggested that STC-1 exhibits broad effects on ion balance, not confines to Ca(2+), but the mechanism of this regulation process remains largely unknown. Here, we used zebrafish embryos as an alternative in vivo model to investigate how STC-1 regulates transepithelial ion transport function in ion-transporting epithelium. Expression of stc-1 mRNA in zebrafish embryos was increased in high-Ca(2+) environments but decreased by acidic and ion-deficient treatments while overexpression of stc-1 impaired the hypotonic acclimation by decreasing whole body Ca(2+), Na(+), and Cl(-) contents and H(+) secretion ability. Injection of STC-1 mRNA also down-regulated mRNA expressions of epithelial Ca(2+) channel, H(+)-ATPase, and Na(+)-Cl(-) cotransporter, suggesting the roles of STC-1 in regulation of ions other than Ca(2+). Knockdown of STC-1 caused an increase in ionocyte progenitors (foxi3a as the marker) and mature ionocytes (ion transporters as the markers), but did not affect epithelium stem cells (p63 as the marker) in the embryonic skin. Overexpression of STC-1 had the corresponding opposite effect on ionocyte progenitors, mature ionocytes in the embryonic skin. Taken together, STC-1 negatively regulates the number of ionocytes to reduce ionocyte functions. This process is important for body fluid ionic homeostasis, which is achieved by the regulation of ion transport functions in ionocytes. The present findings provide new insights into the broader functions of STC-1, a hypocalcemic hormone.
- Published
- 2015
- Full Text
- View/download PDF
295. Factors affecting calcium balance in Chinese adolescents
- Author
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Qian Zhang, Ailing Liu, Xiaoyan Wang, Guansheng Ma, Jing Yin, Weijing Du, and Xiaoqi Hu
- Subjects
Male ,medicine.medical_specialty ,Histology ,medicine.risk_factor ,Adolescent ,Physiology ,Endocrinology, Diabetes and Metabolism ,Elemental calcium ,chemistry.chemical_element ,Urine ,Calcium ,Calcium Carbonate ,chemistry.chemical_compound ,Internal medicine ,medicine ,Humans ,Calcium metabolism ,business.industry ,Bioavailability ,Calcium, Dietary ,Spermatorrhea ,Calcium carbonate ,Endocrinology ,Intestinal Absorption ,chemistry ,Dietary Reference Intake ,Dietary Supplements ,Female ,business - Abstract
Chinese dietary reference intakes (DRIs) for calcium were developed mainly from studies conducted amongst Caucasians, yet a recent review showed that reference calcium intakes for Asians are likely to be different from those of Caucasians (Lee and Jiang, 2008). In order to develop calcium DRIs for Chinese adolescents, it is necessary to explore the characteristics and potential influencing factors of calcium metabolic balance in Chinese adolescents. A total of 80 students (15.1+/-0.8 years) were recruited stratified by gender from a 1-year calcium supplementation study. Subjects were randomly designed to four groups and supplemented with calcium carbonate tablets providing elemental calcium at 63, 354, 660, and 966 mg/day, respectively. Subjects consumed food from a 3-day cycle menu prepared by staff for 10 days. Elemental calcium in samples of foods, feces, and urine was determined in duplicates by inductively coupled plasma atomic emission spectrometry. The total calcium intake ranged from 352 to 1323 mg/day. The calcium apparent absorption efficiency and retention in boys were significantly higher than that in girls (68.7% vs. 46.4%, 480 mg/day vs. 204 mg/day, P
- Published
- 2010
296. P.2.103 Calcium balance and regulation in patients with diagnosis of schizophrenia treated with second generation antipsychotics
- Author
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A.W.K. WyszogrodzkaKucharska
- Subjects
Pharmacology ,medicine.medical_specialty ,Calcium balance ,business.industry ,Psychiatry and Mental health ,Neurology ,Internal medicine ,medicine ,Pharmacology (medical) ,In patient ,Neurology (clinical) ,Psychiatry ,business ,Biological Psychiatry ,Diagnosis of schizophrenia - Published
- 2004
297. Calcium balance inDaphniagrown on diets differing in food quantity, phosphorus and calcium
- Author
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Wen-Xiong Wang and Xuejia He
- Subjects
biology ,Chemistry ,Phosphorus ,Daphnia magna ,chemistry.chemical_element ,Aquatic Science ,Calcium ,biology.organism_classification ,Daphnia ,Excretion ,Nutrient ,Animal science ,Biochemistry ,Epilimnion ,Moulting - Abstract
Summary 1. The influences of dietary phosphorus (P) and food concentration on the calcium (Ca) balance in Daphnia magna were examined in this study at two different ambient Ca concentrations (0.5 and 10 mg Ca L−1). Daphnia were grown by feeding the young adults differentially under contrasting dietary P conditions [molar C : P ratio = c. 900 and c. 90 as low P (LP) and high P (HP), respectively], ambient Ca concentrations [0.5 mg and 10 mg Ca L−1 as low Ca (LCa) or high Ca (HCa), respectively] and food levels [0.15 or 1.5 mg C L−1 as low food (LF) or high food (HF), respectively] for 5 days. 2. The specific Ca contents of daphniids (1.9–6.5% of dry weight−1) increased with increasing Ca concentration, food level and dietary P content, although the food level did not affect the Ca content in the HPHCa treatment. A radioactive tracer method showed that the food level did not affect the influx of Ca from the water under LP conditions, but the Ca influx under HP conditions doubled with a HF level. A LP condition also led to a decrease in Ca influx with a HF level. 3. During the 3 days of efflux, generally only a small proportion of Ca (2.6–3.3%) was retained by the daphniids, but this retention increased (14–23%) under low ambient Ca concentrations and under P-limitation. Excretion was the most important pathway for Ca loss (accounting for 50–60% of body Ca), followed by moulting (20–47%), but the relative contribution of these two pathways (excretion and moulting) did not vary among all the different treatments. The absolute loss of Ca through excretion and moulting, on the contrary, differed with different ambient Ca concentrations and dietary P conditions. A HF level led to an increase in the loss rates in most cases. 4. Our study strongly suggested that there is an interaction between an essential metal (Ca) and macronutrients (C and P) in freshwater crustaceans with HCa and P contents. The results imply that variation in environmental nutrient conditions may change the Ca budget in crustaceans and may affect the dynamics of Ca in the epilimnion of freshwaters.
- Published
- 2009
298. Ethanol Extract of Fructus ligustri lucidi Increased Circulating 1,25(OH)2D3Levels, but Did Not Improve Calcium Balance in Mature Ovariectomized Rats
- Author
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Dong, Xiao-Li, primary, Cao, Si-Si, additional, Zhou, Li-Ping, additional, Denney, Liya, additional, Wong, Man-Sau, additional, and Feng, Hao-Tian, additional
- Published
- 2016
- Full Text
- View/download PDF
299. Calcium balance, growth and skeletal mineralisation in patients with cystoplasties
- Author
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D. E. Nurse and Anthony R. Mundy
- Subjects
medicine.medical_specialty ,Calcium balance ,Urology ,Urinary Bladder ,chemistry.chemical_element ,Calcium ,Respiratory compensation ,Bone and Bones ,Absorptiometry, Photon ,Calcification, Physiologic ,Postoperative Complications ,Internal medicine ,medicine ,Arterial blood gas analysis ,Humans ,In patient ,Child ,Retrospective Studies ,Urinary bladder ,Bone Development ,business.industry ,Metabolic acidosis ,Middle Aged ,medicine.disease ,Urinary calcium ,Endocrinology ,medicine.anatomical_structure ,chemistry ,Child, Preschool ,Female ,business ,Acidosis - Abstract
Summary Twelve adult female patients and 16 children who had undergone augmentation cystoplasty at least 2 years previously were studied to assess calcium balance and skeletal mineralisation. The serum and 24-h urinary calcium levels were measured and arterial blood gas analysis was performed in all patients. In children, skeletal mineralisation was assessed by serial study of their growth charts, comparing their growth centiles before and after cystoplasty. In adults, skeletal mineralisation was assessed by dual photon absorptiometry (DPA). As previously reported, all patients had a metabolic acidosis, usually with respiratory compensation. Serum and 24-h urinary calcium levels were all within the normal range. Growth charts of the 6 children with colocystoplasties showed an average of 20% reduction in growth potential in 3 of them. Growth charts in the 10 children with ileocystoplasties did not show any change in growth pattern. DPA bone scans in adults were all normal. These results suggest that if calcium is mobilised from bone in patients with a cystoplasty as a result of the metabolic acidosis, then it is reabsorbed from the bladder by the gut segment after an ileocystoplasty; colonic segments are less efficient than ileal segments, however, so that after a colocystoplasty skeletal demineralisation or a reduction in growth potential is more likely.
- Published
- 1992
300. Calcium balance in pediatric online hemodiafiltration: Beware of sodium and bicarbonate in the dialysate
- Author
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Bacchetta, Justine, primary, Sellier-Leclerc, Anne-Laure, additional, Bertholet-Thomas, Aurélia, additional, Carlier, Marie-Christine, additional, Cartier, Régine, additional, Cochat, Pierre, additional, and Ranchin, Bruno, additional
- Published
- 2015
- Full Text
- View/download PDF
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